This invention relates to wire spoke wheels and particularly to such wheels especially suitable for use with conventional tubeless tires and which are sturdy and durable.
Heretofore, wire spoke automobile wheels which permit the use of tubeless tires have been difficult and costly to construct. A typical method of manufacture resulted in the projection of wheel spoke nipple ends through holes in a rim drop center, which often interfered with maintaining a reliable and effective airtight seal in the tire. In an effort to overcome this seal problem, structures have been suggested utilizing spoke ends which are connected to a felly mounted concentrically inwardly of the rim drop center. This makes a reliable mounting for tubeless tires, but is often complex and expensive to produce. Further, neither arrangement effectively confronts the problems associated with the use of "suspension" type wire spoke wheels; namely, that suspension wire wheels must be originally tension aligned or "tuned" and are subject to subsequent slackening or "detuning" of spokes after periods of use or after striking resisting obstacles such as curbs, chuckholes and the like.
Moreover, the cost of manufacturing suspension wire wheels is inherently quite high because considerable handwork is required during the assembly and spoke tuning processes. Thus, a typical suspension conventional wire wheel may cost substantially more than a non-wire spoke and decorative wheel, while being less durable.
Within the past few years, certain automotive wheel manufacturers have attempted to overcome the problems associated with wire suspension wheels by employing relatively rigid and non-tensioned bars extending radially between the hub and rim. Though functionally effective, these bars are generally substantially heavier or thicker than wire wheels and have not had the consumer demand of conventional suspension wire spoke wheels.
As referred to in this application the phrases "suspension" wire wheels and "tensioned" wire wheels signify a wire wheel having a rim and a hub with the rim floating inside the hub on wire spokes that are operably tensioned. The tension in each individual spoke can and must be adjusted to tune the wheel.
The phrases "non-tensioned" wire spoke wheel, "untensioned" wheel, and "non-suspension" wheel signify a wheel having a rim and hub wherein the hub is supported by rigid non adjustable spokes which are positioned between the hub and the rim. The spokes in this style of wheel encounter no axial forces prior to the supporting of any weight by the wheel. In the "suspension" type wire wheel there exists an axial tensile force in the spokes while the wheel is in an unloaded condition.
In general the wire wheel assembly of the present invention has been extensively described in the previously mentioned parent applications of the present application and the disclosure contained in those parent applications is included herein by reference. In the parent applications a wheel is described wherein a felly was mounted concentrically inward of the rim drop center in conjunction with operably untensioned spokes which are partially recessed into bores placed circumferentially around the felly. The bores have an inner section and an outer section with the outer section having a greater diameter than the inner section, thereby forming a shoulder at their juncture. The outer end of each spoke is placed in a respective bore so as to extend radially into the felly to the shoulder. The spokes are then anchored to the felly by an electric current welding process, the accumulation from which forms a plug anchor on the outer end of the spokes which plug is of a larger diameter than the diameter of the inner section of the bore thereby preventing the spoke from being pulled inwardly relative to the felly toward the wheel hub. After the felly is secured to the rim, the spoke is prohibited from movement outwardly relative to the felly by the rim.
While the above described method of manufacturing such a wheel produces a high quality and consumer acceptable wheel, the process of drilling and counter drilling the bores tends to be labor intensive.
Also, previous untensioned wheels have typically not had the exact appearance of the suspension wire wheel in that suspension wire wheels historically have had dimples extending inwardly from the rim at a position whereat the outer end of the spoke is attached to the rim. In suspension type wheels, the dimples are utilized to form a pocket or receptacle for an associated nipple which holds the spoke onto the suspension type rim so that the nipple does not extend radially outwardly from the rim and interfer with forming a seal between the rim and a tire. Thus, in suspension wheels the nipple is located in an associated inwardly projecting dimple which positions the top of the nipple flush with remainder of the rim. A substance is placed inside the rim to seal same, therefore making the sealing of a tire on such a rim much easier.
In addition, prior operably untensioned spoke wheels have typically differed in appearance from suspension wire wheels in that exterior portions of the nipples which hold the ends of the spokes to the rim are threadably attached to respective spokes and have flats on the outer circumferential surface thereof which allow the nipple to be tuned by a suitable tool thereby loosening or tightening the spoke. In general, previous non-suspension spoke wheels have not provided for nipples flats, with the result of reducing customer satisfaction in the appearance of such wheels.